The device I primarily had in mind is tillitis' TKey. Essentially a general purpose (slow) processing unit. The secret is 32-bytes long and given no storage, that's essentially all you work with. However, the secret is dependent on device + program-binary + 32-byte-user-secret.
A certificate is also a secret + certified public key, right? So, if you cannot store the certification on the TKey (no persistence) than you're left with the same construction. Right now, I'm skipping the complexity of certs (PKCS11, IIRC) etc. The identity being persistent is in order to authenticate the device.
A certificate is also a secret + certified public key, right? So, if you cannot store the certification on the TKey (no persistence) than you're left with the same construction. Right now, I'm skipping the complexity of certs (PKCS11, IIRC) etc. The identity being persistent is in order to authenticate the device.